1. Field of the Invention
The present invention relates to tools for use with motor vehicles. More particularly, it relates to a portable tool for use in disconnecting power and air lines between a motor vehicle, such as a truck cab, and a trailer that is towed by the motor vehicle, or some form of utility hookup apparatus.
2. General Background and State of the Art
The economies of our developed industrial nations rely heavily on the transport of goods by trucks and truckers. Many trailers that are towed by a truck, because of the nature of the goods they carry, require both power and air. Truck/trailer combinations actually have two air lines, one for service and one for the parking brake (a safety feature on modern trucks).
During the last several years, travel by recreational vehicle (RV) has become increasingly popular. Nationwide, there are numerous camp grounds that provide space for persons traveling by RV that include hookups for power. That way, when a person or persons wants to camp for the night, they have ready access to necessary power for their comfort. Recently, RV's, especially large ones, have switched to air powered brakes and air assisted electrical and hydraulic brakes on trailers towed by them.
The typical way of hooking up a motor vehicle and trailer for power is to plug a female connector on the end of an electrical cable from the motor into a socket having connector pins that is mounted in the wall of a trailer. The connector pins in the trailer are protected by a hinged plate that covers the pins when the trailer is not hooked to the motor vehicle's electrical system. The hinged cover plate is moved up and away from the socket when the electrical system of the trailer is hooked up to the electrical system of the vehicle.
Electrical wires that connect to the electrical system of the trailer are connected to pins that are mounted on the inside of the trailer wall just behind the electrical socket assembly. These pins are in electrical communication with the pins in the socket assembly.
Air lines between trucks or motor vehicles and trailers are generally joined by locking flanges found mounted on the trailer wall and corresponding locking flanges found on the air lines from the truck. This kind of structure is generally known as “glad hands.”
The electrical lines connecting commercial trucks to trailer systems or RV's to campground utility system are usually disengaged from each other by pulling the trailer socket and the vehicle plug portions away from each other by hand. This procedure can be difficult on a person's hands and can easily cause injury. Often, after a lengthy trip, the socket and plug portions can be very dirty and can cause a mess. Some of the dirt and grime collected on the electrical connectors could infiltrate the body through an opening in the skin and cause illness or infection.
Another problem associated with manually separating the trailer electrical socket and plug on a motor vehicle is that the process of pulling the two apart frequently includes “wiggling” of the socket and plug, which may lead to the wires in the trailer being separated from the connector pins. Thus, some of the trailer's lights may not receive electricity or the supply of electricity will be interrupted, causing the trailer lights to blink or become inoperable. This result can lead to traffic citations being handed out to truckers as they carry out their work. It may also lead to a potentially dangerous situation on the road under conditions of low visibility, such as in heavy rain, snow, or dense fog.
The inventor knows of only two attempts to devise a way to disconnect the electrical connectors between a commercial truck cab and a trailer that differs from the manual procedure. U.S. Pat. No. 4,784,610 discloses a tool permanently attached to the electrical connection socket of a trailer. To disconnect the truck electrical line from the electrical system of the trailer, a person grasps the tool by its handle and by applying leverage against the plug can pull the handle away from the trailer causing the plug and socket to separate. The tool disclosed in Stuart is permanently attached to the trailer and cannot be stored in the truck cab, nor can the tool be used to separate the air lines between the truck cab and the trailer. Furthermore, it cannot be adapted for use on all models of trailer.
Co-owned U.S. Pat. No. 6,957,478 (the '478 patent) discloses a portable tool that could be used for the purpose of separating the utility lines between a trailer and a motor vehicle. The tool in the '478 patent incorporated a spring mounted push bar for leverage and a lifting bar to raise the hinged cover of the trailer's electrical socket assembly. Pushing the curved handle of the tool towards the electrical socket will cause the plug and socket to separate, without the possibility of the electrical wiring in the trailer becoming disconnected.
The present invention provides a novel tool that includes many of the advantages of the invention disclosed in the '478 patent and includes other advantageous aspects not known in the prior art.